Derlin-1 Promotes the Progression of Human Hepatocellular Carcinoma via the Activation of AKT Pathway

Comparative Quantitative Proteomic Analysis of Melanoma Subtypes, Nevus-Associated Melanoma, and Corresponding Nevi

A substantial part of cutaneous malignant melanomas develops from benign nevi. However, the precise molecular events driving the transformation from benign to malignant melanoma are not well-understood. We used laser microdissection and mass spectrometry to analyze the proteomes of melanoma subtypes, including superficial spreading melanomas (n = 17), nodular melanomas (n = 17), and acral melanomas (n = 15). Furthermore, we compared the proteomes of nevi cells with those of melanoma cells within the same specimens (nevus-associated melanoma (n = 14)). In total, we quantified 7935 proteins. Despite the genomic and clinical differences of the melanoma subtypes, our analysis revealed relatively similar proteomes, except for the upregulation of proteins involved in immune activation in nodular melanomas versus acral melanomas. Examining nevus-associated melanoma versus nevi, we found 1725 differentially expressed proteins (false discovery rate < 0.05). Among these proteins were 140 that overlapped with cancer hallmarks, tumor suppressors, and regulators of metabolism and cell cycle. Pathway analysis indicated aberrant activation of the phosphoinositide 3-kinase-protein kinase B-mTOR pathways and the Hippo-YAP pathway. Using a classifier, we identified six proteins capable of distinguishing melanoma from nevi samples. Our study represents a comprehensive comparative analysis of the proteome in melanoma subtypes and associated nevi, offering insights into the biological behavior of these distinct entities.

miR-181c-5p/DERL1 pathway controls breast cancer progression mediated by TRAF6-linked K63 ubiquitination of AKT

BACKGROUND

Aberrant Derlin-1 (DERL1) expression is associated with an overactivation of p-AKT, whose involvement in breast cancer (BRCA) development has been widely speculated. However, the precise mechanism that links DERL1 expression and AKT activation is less well-studied.

METHODS

Bioinformatic analyses hold a promising approach by which to detect genes' expression levels and their association with disease prognoses in patients. In the present work, a dual-luciferase assay was employed to investigate the relationship between DERL1 expression and the candidate miRNA by both in vitro and in vivo methods. Further in-depth studies involving immunoprecipitation-mass spectrum (IP-MS), co-immunoprecipitation (Co-IP), as well as Zdock prediction were performed.

RESULTS

Overexpression of DERL1 was detected in all phenotypes of BRCA, and its knockdown showed an inhibitory effect on BRCA cells both in vitro and in vivo. The Cancer Genome Atlas (TCGA) database reported that DERL1 overexpression was correlated with poor overall survival in BRCA cases, and so the quantification of DERL1 expression could be a potential marker for the clinical diagnosis of BRCA. On the other hand, miR-181c-5p was downregulated in BRCA, suggesting that its overexpression could be a potent therapeutic route to improve the overall survival of BRCA cases. Prior bioinformatic analyses indicated a somewhat positive correlation between DERL1 and TRAF6 as well as between TRAF6 and AKT, but not between miR-181c-5p and DERL1. In retrospect, DERL1 overexpression promoted p-AKT activation through K63 ubiquitination. DERL1 was believed to directly interact with the E3 ligase TRAF6. As Tyr77Ala or Tyr77Ala/Gln81Ala/Arg85Ala/Val158Ala attempts to prevent the interaction between DERL1 and TRAF domain of TRAF6, resulted in a significant reduction in K63-ubiquitinated p-AKT production. However, mutations in Gln81Ala, Arg85Ala, or Val158Ala could possibly interrupt with these processes.

CONCLUSIONS

Our data confirm that mediation of the miR-181c-5p/DERL1 pathway by TRAF6-linked AKT K63 ubiquitination holds one of the clues to set our focus on toward meeting the therapeutic goals of BRCA.

DERL2 (derlin 2) stabilizes BAG6 (BAG cochaperone 6) in chemotherapy resistance of cholangiocarcinoma

DERL2 (derlin 2) is a critical component of the endoplasmic reticulum quality control pathway system whose mutations play an important role in carcinogenesis, including cholangiocarcinoma (CHOL). However, its role and its underlying mechanism have yet to be elucidated. Herein, we revealed that DERL2 was highly expressed in CHOL and considered as an independent prognostic indicator for inferior survival in CHOL. DERL2 ectopically expressed in CHOL cells promoted cell proliferation and colony formation rates, and depleting DERL2 in CHOL cells curbed tumor growth in vitro and in vivo. More interestingly, the knockout of DERL2 augmented the growth-inhibitory effect of gemcitabine chemotherapy on CHOL cells by inducing cell apoptosis. Mechanistically, we discovered that DERL2 interacted with BAG6 (BAG cochaperone 6), thereby extending its half-life and reinforcing the oncogenic role of BAG6 in CHOL progression.

TOLLIP-mediated autophagic degradation pathway links the VCP-TMEM63A-DERL1 signaling axis to triple-negative breast cancer progression

Triple-negative breast cancer (TNBC) is the most challenging breast cancer subtype to treat due to the lack of effective targeted therapies. Transmembrane (TMEM) proteins represent attractive drug targets for cancer therapy, but biological functions of most members of the TMEM family remain unknown. Here, we report for the first time that TMEM63A (transmembrane protein 63A), a poorly characterized TMEM protein with unknown functions in human cancer, functions as a novel oncogene to promote TNBC cell proliferation, migration, and invasion in vitro and xenograft tumor growth and lung metastasis in vivo. Mechanistic investigations revealed that TMEM63A localizes in endoplasmic reticulum (ER) and lysosome membranes, and interacts with VCP (valosin-containing protein) and its cofactor DERL1 (derlin 1). Furthermore, TMEM63A undergoes autophagy receptor TOLLIP-mediated autophagic degradation and is stabilized by VCP through blocking its lysosomal degradation. Strikingly, TMEM63A in turn stabilizes oncoprotein DERL1 through preventing TOLLIP-mediated autophagic degradation. Notably, pharmacological inhibition of VCP by CB-5083 or knockdown of DERL1 partially abolishes the oncogenic effects of TMEM63A on TNBC progression both in vitro and in vivo. Collectively, these findings uncover a previously unknown functional and mechanistic role for TMEM63A in TNBC progression and provide a new clue for targeting TMEM63A-driven TNBC tumors by using a VCP inhibitor.Abbreviations: ATG16L1, autophagy related 16 like 1; ATG5, autophagy related 5; ATP5F1B/ATP5B, ATP synthase F1 subunit beta; Baf-A1, bafilomycin A₁; CALCOCO2/NDP52, calcium binding and coiled-coil domain 2; CANX, calnexin; DERL1, derlin 1; EGFR, epidermal growth factor receptor; ER, endoplasmic reticulum; ERAD, endoplasmic reticulum-associated degradation; HSPA8, heat shock protein family A (Hsp70) member 8; IP, immunoprecipitation; LAMP2A, lysosomal associated membrane protein 2; NBR1, NBR1 autophagy cargo receptor; OPTN, optineurin; RT-qPCR, reverse transcription-quantitative PCR; SQSTM1/p62, sequestosome 1; TAX1BP1, Tax1 binding protein 1; TMEM63A, transmembrane protein 63A; TNBC, triple-negative breast cancer; TOLLIP, toll interacting protein; VCP, valosin containing protein.

Associations of selenoprotein expression and gene methylation with the outcome of clear cell renal carcinoma

Selenoproteins are a ubiquitous class of proteins defined by having a selenocysteine amino acid residue. While many of the selenoproteins have been well characterized with important roles in oxidation-reduction reactions and hormone synthesis among others, there exist some whose biological roles are not as well understood as denoted by the "SELENO" root. In this study, we explored associations between the reported RNA levels of "SELENO" proteins and clear cell renal cell carcinoma (ccRCC), the most common subtype of renal carcinoma in the US. Utilizing The Cancer Genome Atlas (TCGA) alongside other in silico tools, we discovered higher mRNA expression of Selenoprotein I, T, and P was associated with better overall survival outcomes and differential expression of other selenoproteins based on tumor stage. Additionally, we uncovered relative hypomethylation among selenoproteins in primary ccRCC tumor samples compared to normal tissue. Network and enrichment analysis showed numerous genes through which selenoproteins may modulate cancer progression and outcomes such as DERL1, PNPLA2/3, MIEN1, and FOXO1 which have been well-described in other cancers. In light of our findings highlighting an association of selenoprotein methylation and expression patterns with ccRCC outcome, further wet lab research is warranted.

Large-scale multiplexed mosaic CRISPR perturbation in the whole organism

Here, we report inducible mosaic animal for perturbation (iMAP), a transgenic platform enabling in situ CRISPR targeting of at least 100 genes in parallel throughout the mouse body. iMAP combines Cre-loxP and CRISPR-Cas9 technologies and utilizes a germline-transmitted transgene carrying a large array of individually floxed, tandemly linked gRNA-coding units. Cre-mediated recombination triggers expression of all the gRNAs in the array but only one of them per cell, converting the mice to mosaic organisms suitable for phenotypic characterization and also for high-throughput derivation of conventional single-gene perturbation lines via breeding. Using gRNA representation as a readout, we mapped a miniature Perturb-Atlas cataloging the perturbations of 90 genes across 39 tissues, which yields rich insights into context-dependent gene functions and provides a glimpse of the potential of iMAP in genome decoding.

Circular RNA circTTBK2 facilitates non-small-cell lung cancer malignancy through the miR-873-5p/TEAD1/DERL1 axis

Aim: The underlying mechanisms by which circular RNAs (circRNAs) regulate non-small-cell lung cancer (NSCLC) progression remain elusive. This study investigated the role of circRNA circTTBK2 in NSCLC tumorigenesis. Materials & methods: Quantitative reverse transcriptase polymerase chain reaction analysis of circTTBK2 in NSCLC tissues and cell lines was performed. Cell proliferation, migration, invasion and tumorigenesis were confirmed in vitro and in vivo using CCK-8, EdU incorporation, Transwell assays and xenograft technique. The circTTBK2/miR-873-5p/TEAD1/DERL1 axis was verified by RNA immunoprecipitation, chromatin immunoprecipitation and luciferase reporter assays. Results: Overexpressed circTTBK2 in NSCLC tissues indicates poor prognosis of NSCLC patients. circTTBK2 harbors miR-873-5p, and miR-873-5p directly targets TEAD1. TEAD1 transcriptionally activates DERL1. Conclusion: This study revealed a novel machinery of circTTBK2/miR-873-5p/TEAD1/DERL1 for NSCLC tumorigenesis.

MicroRNA-375-3p Suppresses Upper Tract Urothelial Carcinoma Cell Migration and Invasion via Targeting Derlin-1

Little is known regarding the molecular characterization of upper tract urothelial carcinoma (UTUC). Novel therapeutic targets and prognostic predictors are imminent. In the present study, we aim to examine the oncogenic function and molecular mechanism of Derlin-1 in UTUC. Derlin-1 overexpression is significantly associated with poor prognosis in patients with UTUC. In vitro, knockdown or over-expression of Derlin-1 markedly regulated UTUC cell invasion and migration. We further discovered miR-375-3p suppresses cell invasion and migration by inversely regulating Derlin-1 and blocking EMT in UTUC cells. Taking this together, miR-375-3p functions as a tumor suppressive microRNA by directly targeting Derlin-1 and blocking epithelial-mesenchymal transition (EMT) in UTUC.

Melatonin enhances cisplatin-induced cell death through inhibition of DERL1 in mesenchymal-like CD44high OSCC cells

BACKGROUND

Melatonin is a hormone that is primarily produced in the pineal gland and is involved in wide range of biological functions. However, the impact of melatonin on chemotherapy-induced cell death remains to be elucidated in oral squamous cell carcinoma (OSCC) cells. The objective of this study was to clarify the role of melatonin in cisplatin-induced cytotoxicity in CD44^high OSCC cells.

METHODS

CD44^high OSCC cells were cultured on fibronectin-coated hydrogel. A lactate dehydrogenase cytotoxicity assay was performed to evaluate cisplatin-induced cell death. The effect of melatonin on cisplatin-induced cell death and Derlin-1 (DERL1) endoplasmic reticulum membrane protein expression was investigated.

RESULTS

CD44^high OSCC cells exhibited mesenchymal-like features when cultured on fibronectin-coated hydrogel. Mesenchymal-like CD44^high OSCC cells demonstrated strong resistance to cisplatin-induced cell death compared with epithelial-like CD44^high OSCC cells. DERL1 mRNA and DERL1 protein expression levels were significantly higher in mesenchymal-like CD44^high cells compared with epithelial-like CD44^high cells. Cisplatin-induced cell death was significantly enhanced after DERL1 siRNA knockdown, suggesting that DERL1 is involved in resistance to cisplatin-induced cell death. Melatonin significantly inhibited DERL1 expression and enhanced cisplatin-induced cell death in mesenchymal-like CD44^high cells. miR-181c-5p expression was significantly upregulated in the presence of melatonin. Furthermore, melatonin-inhibited DERL1 expression was significantly recovered by miR-181c-5p inhibitor. In addition, melatoninenhanced cisplatin-induced cell death was attenuated by miR-181c-5p inhibitor. These results suggest that melatonin-induced miR-181c-5p enhances cisplatin-induced cell death through inhibition of DERL1 in mesenchymal-like CD44^high cells.

CONCLUSIONS

Melatonin plays a vital role in promoting cisplatin-induced cytotoxicity in mesenchymal-like CD44^high OSCC cells.